This invention relates generally to the field of telephony, and more particularly to an improved male base protector module of a type used for the protection of individual subscriber pairs at the point of appearance on a frame-mounted protector block located in a telephone company office. Devices of this general type are well known in the art, and are manufactured at an annual rate of millions per year. The invention lies in specific constructional details which permit improved ease of assembly and lower cost of manufacture using proven prior art electrical components.
These modules are of generally standardized configuration, in each case including an elongated ground pin extending outwardly from a base element, and either four male pins or female sockets accommodating the usual tip in, tip out, ring in, and ring out sides of the line. Depending upon considerations of cost, the required degree of protection, and other factors, such modules will normally include provision for shorting to ground potential, instantaneous voltage and current surges, as well as a heat sensitive means which fires upon the occurence of a sustained current overload. Although gas tubes are most commonly used in the former means, many replacement modules still employ the older carbon arc elements that have been employed since the turn of the century, particularly in connection with the older type connector blocks employed by local telephone companies in other than urban areas. In the case of such replacements, the consideration of cost is paramount, and protection requirements are less demanding.
One factor which permits the production of such low cost modules is the ability to employ certain components used in the manufacture of more sophisticated modules, thereby gaining the advantage of economies of scale. Another is the ability to assemble these components into a completed module using unskilled or semiskilled personnel, with a minimum of effort on the part of the worker. Experience has shown that this may be most readily accomplished where the module is assembled with all of the electrical components in full view, and in which the main housing element which encloses the elements serves only a shielding function.